What is pre-emptive and non-preemptive scheduling?


What is pre-emptive and non-preemptive scheduling?


What is pre-emptive and non-preemptive scheduling? 

Tasks are usually assigned with priorities. At times it is necessary to run a certain task that has a higher priority before another task although it is running. Therefore, the running task is interrupted for some time and resumed later when the priority task has finished its execution. This is called preemptive scheduling.

Eg: Round robin
In non-preemptive scheduling, a running task is executed till completion. It cannot be interrupted.
Eg First In First Out

Operating system - pre-emptive and non-preemptive scheduling - Jan 07, 2010 at 15:00 PM  by Vidya Sagar

What is pre-emptive and non-preemptive scheduling?

Preemptive scheduling: The preemptive scheduling is prioritized. The highest priority process should always be the process that is currently utilized.

Non-Preemptive scheduling: When a process enters the state of running, the state of that process is not deleted from the scheduler until it finishes its service time.


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vishnu 11-10-2014 12:58 PM


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hossain 08-14-2014 10:23 PM

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Anami Destyrius 06-23-2014 02:10 PM



TAZEEM 06-5-2014 03:07 PM

Operating Systems

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Saida Syed 03-16-2014 06:28 AM


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sandeep mishra 09-5-2012 12:37 PM

software engineering

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Tahir Hussain 04-20-2012 06:33 PM

non preemptive scheduling

in non preemptive scheduling, a new process can only come when the current process terminates or it goes to waiting state.

Muhammad Awais 04-18-2012 02:43 AM


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